Re: GIS raster formats

Paul Cooper wrote:

> Well, in lossless compression, I don't think there has been much
> improvement on the venerable LZW technique

This might be true for general lossless data compression (depending on how
you define "much"). But for audio, image and similar special subjects this
is completely false. For example lossless jpeg2000 achieves easily 35%
compression ratio (ie. 100% is no compression) with some rgb images. I
doubt that lzw comes even near with the same images. This is because lzw
doesn't consider the data as an image. There is a lot to take advantage of
when one compresses images instead of just general data.


--
Jani Huhtanen
Tampere University of Technology, Pori
.

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